Fabric contacting circuit closer for knitting machines



Sept. 7, 1948. w c s 2,448,639

FABRIC CONTACTING CIRCUIT CLOSER FOR KNITTING MACHINES Filed Aug. 10,1946 2 Sheets-Sheet 1 INVENTOR Sept. 7, 1948. w c s AN 2,448,639

FABRIC CONTACTING CIRCUIT CLOSER FOR KNITTING MACHINES Filed Aug. 10,1946 2 Sheets-Sheet 2 M/(H/YEL WA (HS/7H INVENTOR BY l Patented Sept. 7,1948 OFFICE FABRIC CQNTACTING CIRCUIT CLOSER FOR KNITTING MACHINESMichael Wachsman, Brooklyn, N. Y.

Application August 10, 1946, Serial No. 689,735

' 1 Claim. 1

The object of this invention is to provide a novel and improved fabriccontacting circuit closer for knitting machines for closing anelectricstop circuit to actuate a knitting machine stopping device when a tear,run, a droppedstitch or other irregular or abnormal condition appears oroccurs in the knitted fabric.

In the operation of knitting machines which include electric circuitclosing devices it is of the utmost importance that such devices be mostcarefully protected against deposits and accumulations of dirt,paraffin, fluff from the fabrics and yarns which unavoidably result fromthe operation of the machines and hinder or even prevent the efiicientoperation of the electric circuit to stop the machine promptly in casesof trouble. It is a prime object of this invention to provide electriccircuit closers in which the contacting terminals are adequatelyenclosed and protected. The invention is embodied in fabric contactingcircuit closers as hereinafter described and as illustrated in theaccompanying drawings in which Fig. 1 is a view of a circuit closerenclosed in a protecting box, the cover of the box being removed.

Fig. 2 is a sectional view of Fig. 1 taken on the line 22 thereof withdetails omitted.

Fig. 3 is a view similar to Fig. 1 but shows a circuit closer having twofabric contacting detectors.

Fig. t shows a circuit closer having a single fabric contacting detectorwith the circuit closing mechanism enclosed in a special innerprotective casing.

Fig. 5 illustrates a modification of the circuit closer shown in Fig. 4.

Fig. 6 shows a circuit closer adapted for high voltage operation toavoid the use of batteries and transformers.

Fig. '7 is a diagrammatic view of circuit closing device in which fabriccontacting detectors eral disclosure and operation of suchdevices'. Aknitting machine is provided with a mechanism for shifting the belt orclutch whereby to -stop the machine when troubles occur. Such mechanismis actuated by an electric circuitwhic'h is normally open. Certainelements inconta'ct with the fabric are employed to close the stopcircuit when abnormal conditions occur in the fabric and suchabnormalities are detected by such elements. This, in brief, is theunderlying principle of operation of knitting machine stop motionswhether they be yarn detectors or 'fabridcontacting detectors.

Referring to the drawings the fabric is represented at it In Fig. 1, adetector I2 is slidably mounted ina box it. The detector carries aninsulated contact l5 which is connected by a spring 7 if: toan-adjustable springsupport ll in'thr'eaded engagement with a screwshaft 18 operable from outside the box by a hand knob [9 to adjust-thetension of the spring. A fixed contact 20 is adjustably mounted in thebox. The contact is movable in a slot 2i and secured by a nut 22 inadjusted position. The contact 29 is completely insulated by insulatingmembers 24 which also serve to close the slot 21 to prevent the entranceof dirt.

The box may have an attaching'lug 25 for mounting the device in asuitable position on the knitting machine. The detector I2 is preferablya thin flat member having a bent contact head 26. The contact 26 isconnected via a battery to an electromagnet 28 which, when energized,operates theshipping lever 38, or clutch lever as the case may be, ofthe usual stop mechanism, not shown. The operation is well known in theart. The other side of the circuit is grounded on the machine.

The detector I2 is held in normal frictional contact with the fabric bythe spring I 6-;- When a fault occurs in'the fabric the spring operatesthe detector to move the contact [5 into-engagement with thecontact 29to close the circuit to energize the magnet'and the knitting machinestops.

Fig. 3 illustrates a device in which twodetectors are mounted in the box[4. In addition to the mechanism shown in Fig. 1, the device in Fig. 3includes a detector 32 which is relatively long and extends upward intocontact with the fabric. Thus a double protection is provided and agreater area of fabric is under control, the detector 32 being offsetwith respect to the detector 12 as shown. The detector 32 is mounted ona shaft 33 under the control of a spring 34 attached to a spring support35 adjustably carried by a screw shaft 36. The shaft 33 also carries acontact 31 two insulated terminals 62 and 63.

adapted to engage a fixed contact 38 which is similar to the contact 26.The operation by either or both detectors i2 and 32 serves to close theelectric circuit to stop the machine.

In Fig. 4 the detecting mechanism includes contact members which arecompletely enclosed within a separate protective casing. In thisillustration the detector 46 is of circular form ending in a pointeddetector head 4!. To the detector is secured a toothed contact member 42in the form of a ring and the detector is urged into contact with thefabric by a spring 13. The contact 42 is grounded on the machine and isadapted to engage a second similar fixed contact M. The latter is whollyinsulated by suitable insulation as at 45, 45. The contact 44 isadjustable with respect to the contact 42 by means of a spring 'll andthreaded nut 48, the spring acting between the casing 46 and the contact&4. The nut 48 carries a terminal 49 for the electric connection to thestop circuit. The entire unit is placed within a box 50 for attachmentto the knitting machine. The casing 46 serves the double purpose ofprotecting the contacting elements against dirt and also in preventingill advised attempts to repair and tamper with the mechanism byunskilledlabor. The casing is preferably made of thin metal and the end52 is soldered to the casing after the other parts have been placedwithin the same.

In the modification illustrated in Fig. the

one ring formed contact member 55 is in the form of a cup having anannular wall 56 adapted to enter a circular groove 57 in the othercontact element 58. The toothed contact elements in Fig. 4 as well asthe elements 55 and 58 inv Fig. 5 afford unusual good contact forclosing the circuit.

In Fig. 6 the electric current supply is direct from the line wires 66to the magnet BI and to The detector 96 may have any suitable form. Itcarries a negative and a positive contact disk 64 and 65, respectively.The disks are insulated as shown at 66 and 6?. The detector with thecontact disks 64 and 65 is held in frictional contact with the fabric I6by a spring 68. The circuit is closed by a contact bridging fixedcontact member 69 which is adjustable by a spring 16 and threaded nut Has shown. The contact 69 is wholly insulated by insulation as at l2, 73.The contact members 64 and 65 have contacting flanges l4 and 15,respectively. 7 When a fault occurs in the fabric the spring 63 operatesthe detector to the right in the drawing. The two flanges M and 75contact with the two terminals 62 and 63, the current passing to the twocontacting disks 64 and 65. The latter are bridged and the circuitclosed by the disks contacting the fixed element 69 as will beunderstood. The entire circuit closing unit is enclosed within adustproof casing 18 and no electric current passes through the knittingmachine. Batteries and transformers are therefore not required.

In Fig. 7 fabric contacting detectors are used 4 on both sides of thefabric. To the usual dial shaft 86 of the knitting machine there issecured an inner contact ring 8i and to the needle cylinder frame,indicated at 82, there is secured an outer contact ring 83. Each ring,Fig. forms an annular chamber 84, Fig. 9, in which there are mounted asmany detectors as may be required. Each detector carries a contact 86and is controlled by a spring 8l. Within each circular chamber at thereis mounted an insulated contact ring 86 to which current is supplied asshown. The detectors are placed in staggered relation as shown in Fig.8.

When a fault occurs in the fabric, one or more tive springs 87 to closethe circuit by engagement of the contacts 86 with the electric ring 88.Obviously, a greater area of fabric may be brought under control by theclosely placed detectors 85.

In Fig. 10, the detector 96 within the box 9| is connected by a chain,wire orlink 94 to the shipping lever 36 so that when the detector isoperated as described above in connection with Fig. 1 not only will thecircuit be closed to actuate the shipping lever, but the latter will bemechanically operated. This feature is provided for double protection inoperation.

The circuit closers disclosed herein may be used with stationary orrotary knitting machines in any combination desired. The enclosing ofthe contacting elements insures freedom from dirt and insures efficientoperation.

I claim:

A fabric contacting circuit closer for knitting machines comprising abox, a detector slidably supported in the box, a spring in said boxsecured to said detector for holding the same in normal frictionalcontact with the fabric, a normally open electric stop circuit for theknitting machine, a fixed contact in said circuit supported in the saidbox, a contact member carried by said detector and adapted to engage thesaid fixed contact to close the said circuit when an abnormal conditionin the fabric causes a termination of the said normal frictional contactbetween the detector and the fabric and means in the said box forregulating the tension of the said spring, said means comprising aspring tension regulating member secured to said spring. a shaft inthreaded engagement with said member to actuate the same and a knob onsaid shaft for operating the later from outside the said box.

MICHAEL WACHSMAN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,286,913 Barratt Dec. 10, 19182,091,467 Carhart Aug. 31, 1937 2,357,712 Vossen et a1 Sept. 5, 1944

